26.7 Hideshow minor mode

Hideshow mode is a buffer-local minor mode that allows you to
selectively display portions of a program, which are referred to as
blocks. Type M-x hs-minor-mode to toggle this minor mode
(see Minor Modes).

When you use Hideshow mode to hide a block, the block disappears
from the screen, to be replaced by an ellipsis (three periods in a
row). Just what constitutes a block depends on the major mode. In C
mode and related modes, blocks are delimited by braces, while in Lisp
mode they are delimited by parentheses. Multi-line comments also
count as blocks.

Hideshow mode provides the following commands:

C-c @ C-h

Hide the current block (hs-hide-block).

C-c @ C-s

Show the current block (hs-show-block).

C-c @ C-c

Either hide or show the current block (hs-toggle-hiding).

S-mouse-2

Toggle hiding for the block you click on (hs-mouse-toggle-hiding).

C-c @ C-M-h

Hide all top-level blocks (hs-hide-all).

C-c @ C-M-s

Show all blocks in the buffer (hs-show-all).

C-c @ C-l

Hide all blocks n levels below this block
(hs-hide-level).

These variables can be used to customize Hideshow mode:

hs-hide-comments-when-hiding-all

If non-nil, C-c @ C-M-h (hs-hide-all) hides
comments too.

hs-isearch-open

This variable specifies the conditions under which incremental search
should unhide a hidden block when matching text occurs within the
block. Its value should be either code (unhide only code
blocks), comment (unhide only comments), t (unhide both
code blocks and comments), or nil (unhide neither code blocks
nor comments). The default value is code.